Private Quantum Channels

We investigate how a classical private key can be used by two players, connected by an insecure one-way quantum channel, to perform private communication of quantum information. In particular, we show that in order to transmit n qubits privately, 2n bits of shared private key are necessary and sufficient. This result may be viewed as the quantum analogue of the classical one-time pad encryption scheme.

Authors

• Andris Ambainis
• Michele Mosca
• Alain Tapp
• Ronald de Wolf

Keywords

• Information security
• Cryptography
• Marine vehicles
• Teleportation
• Ice
• Entropy
• Secret Key
• Symmetric Encryption
• Encryption Scheme
• Hilbert Space
• Mixed State
• Quantum State
• Density Matrix
• Conjugate Transpose
• Tensor Product
• Pure State
• Entangled State
• Pauli Matrices
• Joint State
• Unitary Transformation
• Random Bits
• Quantum Channel
• Bell States
• Secure Way
• Information-theoretic Security